Related Party Transactions - Schedule of Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Related party receivables	$ 335		$ 335		$ 218
Related party liabilities	825		825		1,548
Bank partner agreement \| Financing Partner
Related Party Transaction [Line Items]
Related party receivables	0		0		8
Related party liabilities	0		0		445
Restricted cash	0		0		$ 437
Revenue from Related Parties	26	$ 137	54	$ 216
Related party expenses	$ (211)	$ 26	$ 0	$ 69

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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